During the manufacture and distribution of tapes, an operation takes place in which the tape is wound on a hollow or tubular core. This core is usually made of cardboard, although plastic is used at times. In either case, the core has a smooth outer surface onto which the first layer of the tape must be laid in order to start the winding process. In the case of a tape whose inner surface has no adhesive, it is necessary to apply an adhesive to the core outer surface to cause the tape to adhere. This is true also with a type of tape whose inner surface does bear adhesive, but which adhesive is covered by a release sheet.
In the past, this adhesive has been applied manually with a brush, but this method is considerably less than satisfactory. To begin with, it is awkward to hold the core in one hand, while brushing with the other hand. Adhesive has a tendency to migrate not only to the hand that holds the core, but also to the hand holding the brush. Furthermore, the brushing method results in an uneven layer of adhesive that can result in problems during subsequent operations, including that of winding. For instance, in transporting a number of cores from the adhesive-application station to the winding station, an unstructured layer of adhesive can cause the cores to stick to one another and to the container in which they are carried. Another method that has been used in the past involves loading the cores on the re-wind mandrel of a slitter, starting the machine, rotating the cores on the mandrel, and then using a tape application gun to transfer adhesive to the cores. If one attempted to apply the adhesive to the core while it is in the winding machine, it would not only take time from the actual winding operation, but also cause problems related to entry of adhesive into the machine and the accidental application to the completed coil of tape.
The prior art is replete with constructions for applying coatings or labels to articles during manufacture. One of the methods consists of carrying the coating or label on a moving belt and then advancing the article toward the belt and into contact with the coating or article on the belt. For instance, the U.S. Pat No. 4,484,574 of DeRusha shows the application of an adhesive layer to a foam tape, followed by winding the resultant combination into a roll. The U.S. Pat. No. 3,389,009 of McNulty teaches the continuous application of a coating to the surface of a conduit while passing its surface over a tape that carries the coating in a powdered form. The U.S. Pat. No. 4,484,970 of Burzlaff teaches the application of a decorative foil to an article by applying adhesive to the foil and then pressing the foil on the surface of the article. Similarly, in the U.S. Pat. No. 3,709,755 of Wochner labels are carried on a belt and a container is brought into contact with a label. The U.S. Pat. No. 3,816,207, of Robertson et al shows a design applied to a cylindrical article by running a tape over its surface and heat-pressing the design from the tape onto the article. The U.S. Pat. No. 4,713,128 of Kerwin shows an article mounted on a mandrel, while a tape that carries a decal moves past it and is moved toward the tape to bring the decal into adhering contact with the article.
The prior art systems are rather complicated and expensive and do not lend themselves to the application of adhesive to cores for tape rolls. In small tape-manufacture and winding facilities, it is desirable to have an adhesive applicator that is portable, so that it can be moved from place to place, but the prior art machines are designed for permanent installation. In many cases, the prior art machinery is automatic and, therefore, is capable of injuring the operator. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.
It is, therefore, an outstanding object of the invention to provide an adhesive applicator that facilitates the application of adhesive to a core surface in such a way that a uniform layer results.
Another object of this invention is the provision of an applicator for adhesive which is uncomplicated and combines the best features of manual and automatic operation.
A further object of the present invention is the provision of an adhesive applicator that is not dangerous to use.
A still further object of the invention is the provision of an adhesive coating machine that is light in weight and can be carried from one location to another without difficulty.
It is a further object of the invention to provide an adhesive application device that prepares cores in a particularly uniform manner for subsequent effective use in a winding machine.
Another object of the invention is the provision of an adhesive applicator which is simple and rugged in construction, which can be easily manufactured from readily-available materials, and which is capable of a long life of useful service with a minimum of maintenance.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.